I used to have a Goal Zero nomad 7 with the AA battery pack. It worked great at the house the few times I tried it. Out in the woods however, it didn't work like at home. I couldn't find a spot that was in the sun all day, so I did the best I could. The idea was it would charge the AA batteries during the day and then in camp at night I would swap out the ones in my headlamp, GPS, charge my phone, whatever I needed. What I found was that unless I stayed in camp and kept it in full sun all day, it wasn't charging the batteries fully, even if I let it go for 2 days. It was a total disappointment. I returned it to REI and then purchased a 20,000mah battery pack from Amazon for about $40. The battery pack is perfect for me. I swapped all of my devices to rechargeable (via USB) and that was a bit of an investment, but they were all things I wanted to upgrade anyways (headlamp, GPS, micro lantern, steripen, InReach, and phone). Best of all, it weights about the same, but packs a lot easier.